Circulating valves

ABSTRACT

A valve for controlling the circulation of condensate in which two telescopically disposed shells are interposed between the inlet and the outlet of the valve, one of said shells being movable in axial direction relative to the valve body, the other being rotatable about its axis, the sidewalls of the shells having ports for the throughflow of the condensate, the opening of said ports being controlled by said axial and said rotational movement of said shells.

llited States Patent 1151 3,60,31 l Gotzenberger Feb. 8, 197 2 [54]CIRCULATING VALVES [56] References Cited [72] Inventor: RudibertGotzenberger, Fellbach, Ger- UNITED STATES PATENTS man y 2,100,49411/1937 Sparks 062/224 1 Asslgneer Ernst Flllsch, Fellbach, Germany3,299,829 1/1967 Jackson et al ..91/375 x Banner X [21] Appl. No.:31,916 FOREIGN PATENTS OR APPLICATIONS 780,191 7/1957 Great Britainl37/637.4 Relmd Apphcam Data 315,577 4/1937 France ..91/375 [63]Continuation-impart of Ser. No. 712,457, Mar. 12,

1968, abandoned. Primary Examiner-Robert G. Nilson Attorney-Nolte &Nolte [30] Foreign Application Priority Data Mar. 15,1967 Germany ..F51817 [57] ABS CT A valve for controlling the circulation of condensatein which [52] U.S. Cl ..l37/637.4, 137/599, 137/613, two telescopicallydisposed shells are interposed between the 62/224 inlet and the outletof the valve, one of said shells being mova- [51] llnt. Cl ..Fl6k 31/145 ble in axial direction relative to the valve body, the other being[58] Field of Search ..137/625.17, 637.4; 62/224; rotatable about itsaxis, the sidewalls of the shells having ports 91/375 for thethroughflow of the condensate, the opening of said ports beingcontrolled by said axial and said rotational move ment of said shells.

7 Claims, 3 Drawing Figures 1 A I I v" l/y 5 7 I a 4/ I I b 32 21 20 \l28* l 22 PATENIEU FEB 8 I172 SHEET 1 OF 2 Fig. 1

INVKNTOK RUDIBERT (XTIZENBBRGER WA rz-v /ML 7.!

PATENTEDFEB we 3640.311

MEI 2 0f 2 ,drmmm CIRCULATING VALVES This is a continuation-in-part ofapplication Ser. No. 712,457, filed Mar. 12, 1968, now abandoned.

This invention relates to temperature-controlled expansion valves forrefrigerants and the like and having inlet and outlet openings for entryand exit of the condensate (e.g., condensed refrigerant) and beingequipped with two telescopically disposed cylindrical shells whosesurfaces are in contact with each other, the shells being provided withopenings to permit the condensate to enter the inner space of the innershell, and with ports in their sidewalls to permit the escape of thecondensate from said inner space into the valve outlet. Atemperature-responsive membrane is provided to actuate axialdisplacement of one of the shells relative to the other whereby therelative location of the escape ports in the walls of the shells ischanged.

This type of valve may be used to control the exact quantity ofrefrigerant to be supplied to the evaporator of a cooling installationsuch as illustrated in U.S. Pat. No. 2,100,494.

The flow of the refrigerant should be controlled in such a way that therefrigerant will fill the evaporator without overflowing.

One of the regulating factors controlling the flow is the evaporatingtemperature which, transformed into pressure, is fed into the expansionvalve.

Known expansion valves of this type cannot be used for a variety ofoutputs of a cooling installation without additional provisions forcorrection of the operation; specifically it is necessary to provide themembrane with a special additional spring when energy due tosuperheating is applied to the membrane. The proper setting of thisspring according to varying condition of operation is usually verydifficult and can be performed by specially trained personnel only.Furthermore, it has to be kept in mind that the vapor pressure of therefrigerant in relation to its temperature is not represented by alinear curve. Consequently, for changing of the force of the springapplied to the membrane for control of the valve, the superheatingtemperatures remain constant only within a very narrow range ofevaporating temperatures.

The principal object of the invention is to avoid and to overcome thedisadvantages of known expansion valves of the type described.

This is achieved by providing two cylindrical shells, one having asmaller diameter and being fitted telescopically into the larger shell,the outside wall of the smaller one being in sliding contact with theinside wall of the larger one, both of these shells being disposedinside of the body of the valve. The two shells are movable relative toeach other in two ways, namely in axial direction and by revolving oneof the shells about its axis. The relative displacement of the twoshells either by an axial movement of one of the shells or by revolvingof one of the shells or a combination of these two movements willinfluence the relative position of the ports in the sidewalls of theshells which in turn will influence the size of the openings in thesidewalls of the two shells.

Thus, the quantity of refrigerant flowing to the outlet of the valve canbe controlled not only by the axial displacement of one of the shellsbut also by revolving of one of the shells and thus the control of theflow of the refrigerant can easier be achieved with much greateraccuracy for any operational condition of the installation.

in a preferred embodiment the outer shell is revolvable about its axis,but remains axially immovable with respect to the valve body. Thisarrangement simplifies the attachment of control means for the revolvingmovement which could be provided in form of a pair of meshing gears ofwhich one would be fixed to and concentric with the outer wall of theouter shell whereas the other would be connected to a handwheel disposedon the outside of the valve body.

The handwheel may be equipped with indicating devices to show theangular displacement of the shell or the size of the opening or thermaloutput of the installation. The degree of accuracy of the control can bedetermined by selecting of the proper gear ratio.

For further improvement of the operation of the valve closing means maybe provided to completely eliminate any flow through the valve. This isadvisable for the following reasons:

To permit relative movement between the telescopically disposed shells,the fit of the two adjacent walls must not be too tight and consequentlysmall quantities of refrigerant under pressure may escape from theinside of the inner shell even if the relative position of the twoshells is such that there is no open escape port in the sidewalls of theshells.

To eliminate this disadvantage, the valve according to the invention maybe provided with a closing means to completely close the flow of therefrigerant into the shells.

Such a closing means may consist basically of a hollow piston disposedinside the valve body and being coaxial with the shells and axiallymovable in the direction towards the opening of the shells. One outersurface of said piston is arranged to close the opening of one of theshells when said piston is axially moved towards the shells. Opposite tothe closing surface, i.e., on the inside of the piston, is a spacedefined by the piston walls, the space being connected to the inlet by acapillary tube. Another tube coaxially disposed inside the piston andinside the inner shell connects the space inside the piston with theoutlet for the refrigerant. A spring is also provided within the pistonbiasing the piston in the closing direction.

When the cooling installation is in operation, the refrigerantcirculates through the valve. The comparatively high pressure of thecondensate entering through the valve inlet acts on the closing surfaceof the piston and is opposed only by the reduced pressure of thecondensate flowing through the capillary opening and acting, togetherwith the spring, against the opposite, i.e., the inner side of theclosing surface.

If operation of the installation is stopped, the action of the membranewill close the ports in the walls of the shells by inducing an axialmovement of the inner shell, and will close the opening of the coaxialtube by actuating a closure thereof. Consequently, there will be no flowof the condensate either through the capillary tube or through thecoaxial tube. No pressure is lost through the capillary tube and thepressure on both sides of the capillary tube becomes equalized.Therefore, the pressure of the spring acting in the closing direction ofthe piston will be the only determining factor for the movement of thepiston. Thus, upon shutting down of the installation, the piston ismoved automatically in the closed position and any throughflow of therefrigerant is completely eliminated. A packing may be provided betweenthe piston and the coaxial tube.

With the inner shell being axially displaceable, the piston mayadvantageously be disposed between the membrane and the shells and theinlet end of the shells may be located close to the piston. It is alsoadvantageous to firmly connect the coaxial tube with the inner shell fortransmitting of the movement of the membrane thereto. The closure forthe outlet end of the coaxial tube is attached to a rod passing throughthe coaxial tube.

The membrane itself does not have to be connected rigidly with thecoaxial tube and the rod. The coaxial tube and the rod or the innershell and the closure may, however, be equipped with springs acting inthe closing direction.

A pusher pin connected at least indirectly with the membrane is providedto transmit the axial movement of the membrane to the coaxial tube andto the rod.

For immediate movement of the piston from its closed to its openposition upon start of the operation of the installation, the axiallymovable shell and the closure for the outlet opening of the coaxial tubeshould be movable for closing operation in the same direction, and theaxially movable shell should be provided with a stop which would preventfurther movement of the shell after all ports have been completelycovered. Thus upon start of the operation the closure of the coaxialtube will open the outlet opening, fluid will stream through thecapillary tube and due to drop of pressure in the capillary tube thepressure exerted on the closing surface of unlvn the piston willovercome the pressure acting against the opposite side of the piston aswell as the pressure of the spring.

A specific embodiment of the present invention will now be describedwith reference to the accompanying drawings, in which:

FIG. 1 is a sectional side elevation of the valve;

FIG. 2 is a cross section through the two shells along line 2-2 of FIG.1; and

FIG. 3 shows diagrammatically an indicator for the control knob ofthevalve.

The valve represented in FIG. 1 and FIG. 2 comprises a valve body 1having an inlet portion 2 and an outlet portion 3 for entry and exit ofthe condensate. A duct 4 connects the outlet and a space 6 beneathmembrane washer 5. A membrane washer spring 7 is disposed betweenmembrane washer and the valve body 1. A cover 50 is fastened by means ofthreads onto the valve housing and is provided with a dome 50a with theinterior of which a capillary tube 51 communicates. The capillary tube51 communicates at its other end in the manner illustrated in US. Pat.No. 2,100,494 with a temperature sensor at the outlet end of theevaporator (not shown) of a refrigeration system. Two coaxial shells 9and 10 are disposed in a sleeve 8. Shell 10, having a smaller diameterthan shell 9, is disposed at least partly within shell 9. Inlet openings13 leading into the inner space 14 of shell 10 are located in the upperend wall thereof close to inlet openings 12 to facilitate entry ofcondensate coming from the inlet 2.

Both shells 9 and 10 have ports 15 disposed in the sidewalls thereof forpermitting the flow of the condensate from the inner space 14 into theannular space 16 and through that space and through the outlet opening17 into the outlet of the valve and therethrough into the evaporator.

The outer shell 9 is revolvable about its axis for adjustment of itsport openings by angular displacement thereof as can best be seen inFIG. 2.

A set of meshing gears consisting of a toothed wheel 18 and toothedwheel 22 is used in connection with a control knob or control wheel 20and spindle 21 for controlling of the revolving movement of the outershell 9 and thereby the angular displacement of the ports.

An indicator of the type as shown in FIG. 3 may be attached to orconnected with the knob 20 to indicate the angular displacement of theports or the degree of opening thereof.

A set screw 24 riding in groove 25 in shell 9 prevents axialdisplacement of the shell 9 without interfering with the revolvingmovement thereof.

The inner shell 10 is movable in axial direction only; the axialmovement being transferred to the inner shell 10 by the tube 27coaxially disposed therewith and firmly connected thereto.

A piston 28 being disposed coaxially with the shells 9 and 10 arelocated in a part 36 of the valve body for axial movement therein has anend portion 29 which serves as a closure for the upper end of the shell9 when the piston is moved in the direction towards the shell. Acapillary opening 30 is provided in the piston wall to permit a limitedflow of the condensate with reduced pressure into the inner space 32 ofthe piston. From there the condensate flows through ports 33 into thetube 27 and through that tube into the outlet of the valve.

The tube 27 and rod 35, located inside of the tube 27 and being coaxialtherewith, extend in an axial direction through the piston 28 andthrough the shells 9 and 10. At the outlet end rod 35 is equipped with astopper 37 which is designed to close the outlet opening of tube 27. Theother end of the rod 35 is equipped with a flange 40 which extendsbeyond the tube 27. When the cooling installation reaches a lowtemperature the medium of comparatively lower pressure will reach themembrane space 6 through the duct 4; the membrane and with it themembrane washer 5 will be deflected downward and with it setscrew 41will also move downwards. In consequence of this movement, a pusher 43is pressed against the flange 40, moving the flange 40 together with rod35 and closure 37 against the biasing force of a spring 44, wherebyclosure 37 opens the bottom opening of tube 27. When clamp 40 has beenlowered to the upper end of tube 27, this tube begins to be lowered,against the biasing force of the spring 46, while the rod and stoppercontinue to be lowered; the bottom opening of tube 27 remains openduring this movement. Thus a small portion of the condensate, whichflows into the valve, can escape through the capillary opening 30 intothe inner space of the piston 28 and from there through ports 33 andthrough tube 27 into the outlet of the valve. The pressure of thecondensate is obviously reduced by passing through the capillary opening30, in consequence of which the pressure in the inner space of thepiston 28 is lower than the pressure of the condensate against the endportion 29 of the piston and thus the piston is kept in its upperposition during the operation of the valve. If, however, theinstallation, of which the valve is a part, is out of operation, themembrane and with it the membrane washer will move upwards inconsequence of which closure 37 and inner shell 10 will also moveupwards thereby closing the bottom opening of tube 27 and the ports 15of the inner shell 10. No condensate can escape and thus pressure willbuild up in the inner space of piston 28 until this pressure equals thepressure acting on the end portion 29 of the piston. The pressure ofspring 45 will operate to move the piston downward whereby the endportion 29 will abut against the rim of outer shell 9 so that nocondensate can escape through any space which might exist between theinner wall of shell 9 and the outer wall of shell 10. The reciprocalmovements of inner shell 10 of rod 35 and of closure 37 thus control themovement of piston 28.

The piston 28 which serves mainly for quick opening and closing duringthe starting and the stopping operation of the installation and whichmay be considered to be a snap piston is biased by spring 45.

The operation of a membrane, which in turn induces the movement of themembrane washer and of parts connected therewith, is well known in theart. The membrane in a valve of the type as used for controlling thecirculation of condensate reacts to changes of pressure of a respectivecontrol fluid acting thereon, the pressure being in a certain relationto the temperature and thus the membrane reacts indirectly to thetemperature changes. The changing pressure of the control fluid, actingon the outside surface of the membrane in a direction which is oppositeto the direction of the pressure of the condensate in membrane space 6against the membrane washer 5, controls the movement of the membrane andwith it the movement of the membrane washer and of parts connectedtherewith.

The valve body consists of two portions revolvable relative to eachother about their axes, namely an upper portion la containing thespindle 21 for the control knob 20 and a lower portion lb containing theoutlet ofthe valve.

By revolving the two portions la and 1b relative to each other, theconnection between the membrane space 6 and the outlet 3 via connectingduct 4 is interrupted and the membrane space may thus selectively beconnected to the outlet 19 communicating with the suction end of therefrigerant conduit adjacent the outlet end of the evaporator (notshown).

While the invention has been described by means of a specificembodiment, I do not wish to be limited thereto, for obviousmodifications will occur to those skilled in the art without departingfrom the spirit of the invention.

What is claimed is:

l. A valve for control of circulation of a condensate, comprising:

membrane means actuable by pressure in response to temperature changes,

an elongated valve body coaxial with the membrane means and having aninlet and an outlet for the condensate,

an outer tubular shell and an inner tubular shell disposed in said valvebody and coaxial therewith, said inner shell being telescopicallydisposed within the outer shell, said shells being axially displaceablein relation to each other, said shells having inlet openings on one oftheir ends for the condensate to enter a space defined by the innerwalls of said inner shell, each of said shells having also ports in saidsidewalls for the flow of the condensate from said space to the outletof the valve,

an axially displaceable tube extending through said shells and beingcoaxial therewith, said tube being firmly attached to said inner shellfor axial displacement thereof,

connecting means between said membrane means said tube for said axialdisplacement of said tube and shell by the membrane means, and

control means operationally connected to the other of said shells forrotational movement of said other shell about its axis, said axialdisplacement of one of said shells and said rotational movement of theother of said shells determining the relative position of the port ofone of said shells to the port of the other of said shells.

2. A control valve as recited in claim 1, also comprising a cylindricalportion of said valve body coaxial with said shells and disposed toreceive said shells.

3. A control valve as recited in claim 1, wherein said control means forrotating said outer shell comprise a spindle rotatably disposed in aportion of said valve body, a control knob disposed on the outside ofsaid valve body and firmly connected to one end of said spindle forrotation thereof, a set of gears having two meshing toothed wheels oneof which being firmly attached to the other end of the spindle, theother wheel being connected to the outer shell for transmittingrotational movement of the knob to the outer shell for alignment of saidports.

4. A control valve as recited in claim 3, also comprising indicatormeans connected with said control knob for indicating the angulardisplacement of the port of the outer shell.

5. A control valve as recited in claim 1 in which said connecting meanscomprises:

a piston movably disposed in said valve body and being coaxial with saidshells but normally removed therefrom, said outer shell having anopening facing said piston, said piston having an outer surface facingsaid opening, said piston having wall means defining an inner spacewithin said piston with an inner surface disposed opposite to said outersurface, capillary conduit means disposed in said wall means andconnecting said inner space with said condensate inlet,

said tube having a first opening connecting the inside of the tube withthe inner space of said piston and a second opening remote from thefirst one connecting the inside of the tube with the outlet of thevalve,

first spring means biasing the piston in the direction of the shellopening, second spring means biasing said tube in the direction of saidmembrane, an axially movable rod disposed coaxially in said tube; thirdspring means biasing said rod in the direction of said membrane, astopper firmly attached to said rod close to one end thereof for closingof said second opening of said tube, and

a pusher interposed between said membrane and said tube and said rod fortransmitting movement of the membrane in one direction to said rod andsaid tube,

said outer surface closing said opening of the outer shell through theaction of the first spring means after the pressure of the condensateacting on the inner surface of the piston has increased by the flow ofcondensate into the inner space of said piston while the ports of theshells and the second opening of said tube have been closed due to thebiasing action of respective springs and in consequence of the movementof the pusher in the direction of the membrane.

6. A control valve as recited in claim 5, also comprising a membranespace defined by the inner walls of said membrane washer and a portionof said valve body, and conduit means connecting said first outlet tosaid membrane space for supply of condensate thereto.

7. A control valve as recited in claim 6, wherein said valve body has anupper portion containing said membrane washer and a lower portioncontaining said first outlet, said upper por-

1. A valve for control of circulation of a condensate, comprising: membrane means actuable by pressure in response to temperature changes, an elongated valve body coaxial with the membrane means and having an inlet and an outlet for the condensate, an outer tubular shell and an inner tubular shell disposed in said valve body and coaxial therewith, said inner shell being telescopically disposed within the outer shell, said shells being axially displaceable in relation to each other, said shells having inlet openings on one of their ends for the condensate to enter a space defined by the inner walls of said inner shell, each of said shells having also ports in said sidewalls for the flow of the condensate from said space to the outlet of the valve, an axially displaceable tube extending through said shells and being coaxial therewith, said tube being firmly attached to said inner shell for axial displacement thereof, connecting means between said membrane means and said tube for said axial displacement of said tube and shell by the membrane means, and control means operationally connected to the other of said shells for rotational movement of said other shell about its axis, said axial displacement of one of said shells and said rotational movement of the other of said shells determining the relative position of the port of one of said shells to the port of the other of said shells.
 2. A control valve as recited in claim 1, also comprising a cylindrical portion of said valve body coaxial with said shells and disposed to receive said shells.
 3. A control valve as recited in claim 1, wherein said control means for rotating said outer shell comprise a spindle rotatably disposed in a portion of said valve body, a control knob disposed on the outside of said valve body and firmly connected to one end of said spindle for rotation thereof, a set of gears having two meshing toothed wheels one of which being firmly attached to the other end of the spindle, the other wheel being connected to the outer shell for transmitting rotational movement of the knob to the outer shell for alignment of said ports.
 4. A control valve as recited in claim 3, also comprising indicator means connected with said control knob for indicating the angular displacement of the port of the outer shell.
 5. A control valve as recited in claim 1 in which said connecting means comprises: a piston movably disposed in said valve body and being coaxial with said shells but normally removed therefrom, said outer shell having an opening facing said piston, said piston having an outer surface facing said opening, said piston having wall means defining an inner space within said piston with an inner surface disposed opposite tO said outer surface, capillary conduit means disposed in said wall means and connecting said inner space with said condensate inlet, said tube having a first opening connecting the inside of the tube with the inner space of said piston and a second opening remote from the first one connecting the inside of the tube with the outlet of the valve, first spring means biasing the piston in the direction of the shell opening, second spring means biasing said tube in the direction of said membrane, an axially movable rod disposed coaxially in said tube; third spring means biasing said rod in the direction of said membrane, a stopper firmly attached to said rod close to one end thereof for closing of said second opening of said tube, and a pusher interposed between said membrane and said tube and said rod for transmitting movement of the membrane in one direction to said rod and said tube, said outer surface closing said opening of the outer shell through the action of the first spring means after the pressure of the condensate acting on the inner surface of the piston has increased by the flow of condensate into the inner space of said piston while the ports of the shells and the second opening of said tube have been closed due to the biasing action of respective springs and in consequence of the movement of the pusher in the direction of the membrane.
 6. A control valve as recited in claim 5, also comprising a membrane space defined by the inner walls of said membrane washer and a portion of said valve body, and conduit means connecting said first outlet to said membrane space for supply of condensate thereto.
 7. A control valve as recited in claim 6, wherein said valve body has an upper portion containing said membrane washer and a lower portion containing said first outlet, said upper portion also containing a second outlet connected to said conduit means, said membrane space being disconnected from said first outlet by movement of said upper portion relative to said lower portion. 